Measurements of thermal conductivities under high pressure in NanTroSEIZE sediment core and several terrestrial rock samples

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http://abstractsearch.agu.org/meetings/2011/FM/T21B-2326.html
Author(s): Tadai, O.; Lin, W.; Hirose, T.; Tanikawa, W.; Mukoyoshi, H.; Matsubayashi, O.; Kanamatsu, T.; Kinoshita, M.
Author Affiliation(s): Primary:
Marin Works Japan, Nankoku, Japan
Other:
Japan Agency for Marine-Earth Science and Technology, Kochi Institute, Nankoku, Japan
National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
Volume Title: AGU 2011 fall meeting
Source: American Geophysical Union Fall Meeting, Vol.2011; American Geophysical Union 2011 fall meeting, San Francisco, CA, Dec. 5-9, 2011. Publisher: American Geophysical Union, Washington, DC, United States
Note: In English
Summary: We examined the effects of high pressure on thermal conductivity in core samples from the slope-apron facies and the upper part of the accretionary prism at drilling site C0001 of The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) and in other samples of five terrestrial rock types. Thermal conductivity clearly increased with increasing pressure for both wet and dry samples. We determined the rate of thermal conductivity change of the NanTroSEIZE sediments to be 0.014 W/mK/MPa when pressure was increased, and 0.01 W/mK/MPa when pressure was decreased. Using the rate determined for decreasing pressure, we estimated that thermal conductivities measured at atmospheric pressure rather than at in situ pressure may be underestimated by 7% for a core sample from around 1 km depth and by 20% for a core sample from around 3 km depth. In general, the rate of thermal conductivity change with pressure showed a positive correlation with porosity. However, the relationship of the rate of thermal conductivity change to porosity is also dependent on the fabric, mineral composition, and pore structure of the sediments and rocks. Furthermore, for Shirahama and Berea sandstones we tested, the effect of pressure on thermal conductivity for dry samples was greater than that for wet samples. To estimate thermal conductivities around the plate boundary in the seismogenic zone of Nankai Trough at about 6-7 km below seafloor, we will measure the thermal conductivity in both core samples of cover sediment and oceanic basalt retrieved from Exp333, IODP under high pressure corresponding to the large depths.
Year of Publication: 2011
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 07 Marine Geology and Oceanography; 18 Geophysics, Solid-Earth; Basalts; Cores; Expedition 315; Expedition 333; Heat flow; IODP Site C0001; Igneous rocks; Integrated Ocean Drilling Program; Mineral composition; NanTroSEIZE; Nankai Trough; North Pacific; Northwest Pacific; Ocean floors; Pacific Ocean; Plate boundaries; Plate tectonics; Porosity; Sampling; Sediments; Thermal conductivity; Volcanic rocks; West Pacific
Coordinates: N331400 N331800 E1364300 E1363800
N324400 N331000 E1365600 E1364000
N331400 N331400 E1364300 E1364300
Record ID: 2015077227
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